Part of Google Plus’s appeal is that it was born of real social network analysis. Paul Adams, formerly of Google and now of Facebook, does research where he has people describe their social networks with post-its and markers, literally drawing out their social mindsets. From his research it’s become clear that we tend to categorize people into groups, and we have different ways of interacting with different groups.

This is nothing groundbreaking – as a matter of fact, early research around internet forums and identity honed in on the way users created an identity that could be separate from who they were offline. But it hadn’t yet been incorporated into social networks in an effective way.

To capitalize on this mental model, Google Plus offers circles. You can define circles however you like, pull in your contacts to any number of circles, and then send your updates to the public, to specific circles or to individuals. Not just friends, family and acquaintances, but location, appropriateness, interests, age, and other filters help users define their circles. Technologist Christopher Allen has systematized his categorization and maintains 42 carefully curated circles. Dante’s circles of hell jokes abound, as do jokey lists.

Circles allow you to better target your messaging – that’s marketing-speak for saying the right thing to the right people. It helps protect you from having that awful picture at the end of a drunken night show up in your boss’s feed, but also helps you in more nuanced ways, as well. I can create circles around my New York food nerd friends who I like to invite to dinner, who may or may not overlap with people I know who would be interested in talking about the nuances of Google Plus’s terms of service. Those who are just interested in oyster happy hours don’t have to hear about internet legalese, and those who are hashing out the legalese with me from Boston or beyond don’t need to see the back-and-forth on what time we’re meeting up for Malpecs in Manhattan.

This also allows for a more fluid sense of identity and a more easy-going conversation. Phil Gillman, head of strategy at an Australian ad agency, says, “It feels very natural in interaction style… It feels less like comment streams and more like conversations.”

There are experts emerging, bringing their social network clout from Twitter and blogs to this new world, who have thousands of followers; they can live in public, while keeping their more personal communications private. This eliminates that Twitter feeling of landing on someone who is meant to be an influencer, and finding their feed full of @-replies that are meaningless to the rest of us. It also means that users are developing curated lists of people to follow, like self-proclaimed tech geek Lynette Young’s Women of Google Plus.

Google Plus also offers Hangouts, video chats where up to ten people can join, and are started by sampling announcing on your stream that you are “hanging out”. Creative uses of hangouts abound – musician Daria Musk plays six- or seven-hour concerts via Hangout, and Lee Allison has scheduled cooking classes where users can buy ingredients in advance and then follow along live. There’s a directory of ongoing hangouts, where you can find something at every hour of the day.

I dropped by another Google Plus phenomenon, the longest hangout ever, started by Mark and Phil Olsen and kept alive by users from around the world for at least two weeks. I found a passionate community, people who knew each other from coming by the hangout. The excitement about being part of the hangout was palpable; it had the feeling of a conference or festival, where things happen spontaneously because people are brought together by a similar passion. Musicians drop by to jam, and tech notables like Michael Dell of Dell computers and Paul Allen, who’s appointed himself the unofficial statistician of Google Plus, share their insights.

When a new network comes on the scene, there’s a collective questioning about the differences between what the new and the prior networks do for us. In the first weeks of Google Plus, users have actively been identifying differences and defining the networks. Is it a Facebook killer, a Twitter killer, or can these happily co-exist? Does Google Plus “seem to be more about a shared present/future connections than about a shared past,” as strategic planner Farrah Bostic said? Does it replace other social networks, or supplement them? All of these discussions are happening in lively form – on Google Plus.

Then there are the doubters, who are skeptical of signing up for yet another social network. I feel you, people. I’m part of social networks I don’t even remember signing up for. My inbox is rife with emails asking me to report what book I’m reading. Every event sign-up seems to have a proprietary social network for announcing where I’ll be, alongside the requisite F and bird. I can check into a location through about six different apps on my phone, all of which interrelate in hazy ways and have one additional almost-meaningful feature that is intended to differentiate it from the rest.

Because of the network effect, we get the most value out of a network where we have the most people in our network. The daunting task of building yet another social network is no fun, and the first harrowing moments in a network, where you and another couple people are shouting into an echo chamber, can be a big turn off. Because Gmail users are already so connected through email, the population of my social network felt seamless and easy, and Google Plus allows a porousness between those in the network and those not, with simple “email the people not in your circles” checkbox.

Google Plus, on the other hand, consolidates and makes social much of what we already do with Google. David Armano, head strategist at an advertising agency and contributor to Harvard Business Review, calls it the social layer, rather than the social network. This will certainly impact our behavior on social networks. Many online articles about Google Plus, like this one, reference people by linking to their profile, providing an additional layer of context to the content. In the long run, Google Plus will be as widely integrated as Facebook and Twitter to allow a single simple mechanism to link virtually everything.

Anita Schillhorn van Veen is a strategist at an advertising agency in NYC and a culture aficionado. You can follow her on twitter at twitter.com/anitasvv

// Marginal Utility

"The social-media companies have largely succeeded in persuading users of their platforms' neutrality. What we fail to see is that these new identities are no less contingent and dictated to us then the ones circumscribed by tradition; only now the constraints are imposed by for-profit companies in explicit service of gain.